Francis l



(ModeL) P. L. BECKER.

DOOR SPRING.

Patented Dec. 14, 1886.

WI TNESSEEI I NITED STATES PATENT FEICE.

FRANCIS L. BECKER, OF NEl/V YORK, N. Y.

DOOR-SPRING.

SPECIFICATION forming part of Letters Patent No. 354,087, dated December14, 1886.

Serial No. 197,665. (Modem T0 aZZ whom, it may concern.-

Be it known that I, FRiNcIs L. BECKER, of the city of New York, countyand State of New York, have invented a new and Improved Door-Spring, ofwhich the following specification isa full, clear, and exactdescription.

This invention relates to a door-spring so made that as the door closesthe force of the spring is increased. As usually made,.the ten sion ofthe spring diminishes gradually as the door closes, and thus when thegreatest force is required the least force is exerted. Therefore thedoor is apt to come to a standstill before being fully closed. I By myinvention this defect is remedied, the greatest force being exerted whenthe door is nearest its closed position.

The invention consists in the various features of improvementhereinafter more fully pointed out.

In the accompanying drawings, Figure 1 is a top view of my improveddoor-spring, showing the door closed. Fig. 2 is a similar View showingit partly open. Fig. 3 is a front view of the device, showing the doorclosed.

The letter A represents a door-frame, and B a door provided with myattachment. It consists of a curved lever, a, having a short arm, a,which is pivoted at or near its center to a base-plate, b, by pin 0. Theshorter arm of the lever a is attached to one end ofa rod, (1, the otherend of which is secured to a bellcrank, e, pivoted to plate I).

f is a coiled spring, secured at one end to bell-crank e, and at theother end to a pin, g, passing through a projection of plate I). Bymeans of a winged nut, h, embracing pin 9, the tension of spring f maybe diminished or increased. If desired, the lever a may be directlyconnected to spring f.

The plate b is attached to the door B by means of a slotted plate, 2',screwed to the door and engaging a pin, j, projecting downward fromplate 6. In this way the attachment may be adjusted nearer to or fartheraway from the door to correspond to moldings on the doorframe. Theattachment thus far described is secured to the door near the top, sothat the horizontal lever a is placed above the upper edge of the door.To the upper edge of the door-frame A there is attached africtionroller, 75, journaled to two lugs, Z, connected to a back plate,m, which is screwed to the doorframe.

a is a light spring, attached with one end to plate I), and. with theother end to the doorframe.

The relative position of the lever a and roller is should be such thatwhen the lever is swung back on opening the doorthe free end of thelever will clear the roller, while when the door is closed the free endof the lever is passed back of the roller. I

The operation of the device is as follows: The door being closed, thelever c is swung forward and rests back of roller is, Fig. 1. On openingthe door, the lever, being forced against roller k, will be turned onits pivot c, and will be swung back until it assumes a positionsubstantially at right angles to that originally occupied. A stop, 0, onplate I) limits the backward motion of the lever. During this motion thespringf will have become distended and will be locked in its distendedposition as soon as the lever to comes to rest against the stop 0, thisbeing the position indicated in Fig. 2. The door may now be further orfully opened without altering the relative arrangement of the parts,excepting to distend the spring a. After the door has been released, thespring a will throw it back sufficiently far to bring the free end oflever a direetly back of roller is. As the end of-the lever now comes incontact with the plate m, it is thrown out of its position of rest, andthe springf will rapidly swing itforward into the position shown inFig. 1. During this motion 'the lever will bear against the roller k,and

thus close the door. it will be observed that during the last-describedmovement of the parts the force with which the lever bears against theroller is continually increased. This is caused by two reasons: First,the free end of the lever passing gradually farther and farther awayfrom the roller, the latter to an even extent approaches the pivot c,and the amount of leverage exerted upon the roller is therebyincreased;secondly, as the shorter lever-arm swings from the position shown inFig. 2 to that shown in Fig.1, the springfis increased in effectiveness,because the shorter lever-arm gradually assumes a position at rightangles to the spring.

It will be seen that the spring it serves to throw the levera intoengagement with roller k, while the spring f serves to operate the partsafter such engagement has been effected.

5 The spring n may possibly be omitted; but then the door must be partlyclosed by hand.

I claim as my invention-- 1. The combination of lugs Z, rigidly attachedto door-frame A and carrying roller Zr, 10 with plate I), attached todoor B, and with curved lever 11, having arm a, pivoted at its center toplate b, and with spring f, connected to arm a,-snbstantially asspecified.

2. The combination of lever a and plate I) Witnesses:

F. v. BRIESEN, ROBT. H. ROY.

